DESCRIPTION: (Applicant?s Abstract) The Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study is an expansion of the Orinda. Longitudinal Study of Myopia (OLSM). The original, single-center study started in Orinda, California in 1989, and the three CLEERE clinics were added during its second phase of funding in 1997. Data on refractive error and the ocular components have been gathered on 1,504 children in Orinda. (90 percent Caucasian), and the expansion to sites in Alabama, Texas, and southern California was motivated by an interest in including African-American, Hispanic, and Asian children. This eight-year lag will result in 11 consecutive years of follow-up data from the Caucasian children and only three years of follow data from the other ethnic groups. Thus, we propose to continue the study at three of the current sites and to terminate the follow-up of children in Orinda. By academic year 2005-06, we will have longitudinal data across eight years for all children, which will enable meaningful comparisons about ocular growth and refractive development as a function of ethnicity. Additionally, we will establish the representativeness of our sample of convenience in Alabama, Texas, and southern California. Participation rates in the CLEERE Study range from 15 percent to 56 percent at these three sites. We propose an annual vision screening of all kindergartners, second, and fifth graders (kindergartners, third, and sixth graders in southern California) in the relevant school districts that participate in the CLEERE Study at the three sites to compare the age and refractive error distributions in participants versus non-participants. We have assembled a database of DNA from 65 Orinda-based myopic children and their families at the University of Iowa. We will continue DNA-based studies on the prevalent OLSM myopes and their families to use these phenotypically well-characterized children and a panel of candidate genes to look for evidence of genetic factors. In parallel with the candidate gene association, family material will be used in an allele sharing approach to identify loci using highly variable, PCR-based markers. We will add this phase to the southern California site for Asian families and to the Alabama site for African-American families. We will continue to examine children in grades I through 8 (ages 6 through 14 years) annually. The measurement of refractive error, the ocular components, accommodative response, accommodative lag, phoria, response AC/A ratio, peripheral refractive error, pushup accommodative amplitude, and intraocular pressure will be performed.